Tobacco



United States Patent )fifice 3,372,701 TOBACCO Claude E. Teague, In, Joseph N. Schumacher, and Wilmer A. Rohde, Winston-Salem, N.C., assignors to R. J. Reynolds Tobacco Company, Winston-Salem, N.C., a corporation of New Jersey No Drawing. Filed Aug. 2, 1965, Ser. No. 476,710 21 Claims. (Cl. 131-117) This invention relates to a tobacco product and has for an object the provision of a composition and process for improving the flavor and aroma of tobacco and tobaceo smoke.

It is well known in the tobacco art that the flavor and aroma of the tobacco product and the smoke from the tobacco are very important considerations in so far as the ultimate consumer is concerned. Considerable efforts are exerted by the manufacturers of tobacco products to provide a product that will be acceptable to the consumer, particularly as regards flavor and aroma characteristics. It has been the common practice in the to bacco industry to prepare blends of domestic and oriental tobaccos in order to provide smoking tobacco which has a pleasing flavor and aroma before and during smoking. However, such a procedure is costly and may 'at times become prohibitive in the event that certain types of tobacco may be in short supply. Accordingly, it is a further object of this invention to provide a new class of additive materials which when applied to the tobacco products improve and enhance the flavor and aroma of these products and the smoke emitted therefrom thereby increasing or enhancing the pleasure and other values that may be derived by the consumer from the use of these products.

A further object of this invention is the provision of a process for enhancing or otherwise improving the fiavor, aroma and other qualities of certain domestic, oriental, reconstituted or synthetic tobaccos which may be deficient in said flavor or aroma or other qualities.

An additional object of this invention is to provide a process of preparing a smoking tobacco or product which when smoked has an enhanced flavor or aroma.

An additional object of this invention is to provide a process of preparing a smoking tobacco or product which when smoked has an enhanced flavor or aroma.

A still further object of this invention is the provision of smoking products, such as cigarettes, cigars or pipe tobacco, and a process for forming same whereby the flavor and aroma before and during smoking are improved or enhanced.

Further and additional objects will appear from the following description and the appended claims.

In accordance with one embodiment of this invention, a tobacco product is provided to which has been added or which has been treated with a small amount of a compound selected from the group of compounds having the general formula:

wherein R is a straightchain alkyl group of from 1 to carbon atoms.

The following specific examples illustrate the preparation and characteristics of representative tobacco additives of the present invention. It will be appreciated, however, that this invention is not limited to the specific process by which the compounds may be prepared. All temperatures are expressed in degrees centigrade.

3,372,701 Patented Mar. 12, 1968 EXAMPLE I Synthesis of 4-hydr0xyhexan0ic acid, 'y-lactone 11.2 grams (0.086 mole) of 4-oxo-hexanoic acid was dissolved in a solution of 3.45 grams (0.086 mole) of sodium hydroxide in 25 milliliters of water. This aqueous solution was further diluted with 25 milliliters of methanol. This solution of the acid salt was then added to a stirred solution of 1.2 grams of sodium borohydride in 25 milliliters of methanol and stirred at room temperature for 1.5 hours. The reaction mixture was then hydrolyzed with 10% hydrochloric acid to pH 4. The acidic solution was stirred for an additional one hour after which most of the methanol was removed under aspirator pressure. The aqueous solution was then extracted with ether and the ether solution was washed with 2 x 25 milliliters of 10% sodium bicarbonate followed by a wash with water and then dried. Removal of ether left 8 grams of yellow liquid whose infrared spectrum indicated it to be essentially pure 4-h-ydroxyhexanoic acid y-lactone. Distillation of the crude lactone provided 6.9 grams of pure water-white lactone, boiling point 55/1 millimeter of mercury. The title compound has the following formula:

EXAMPLE II The compound 4-hydroxyoctanoic acid, 'y-lactone is prepared by the procedure of Example I using 4-oxooctanoic acid in lieu of the 4-oxo-hexanoic acid. This compound has the formula:

0113-0 HzC Ha- CHrL O EXAMPLE III The compound 4-l1ydroxynonanoic acid, 'y-lactone is prepared by the procedure of Example -I using 4-oxonon'anoic acid in lieu of the 4-oxo-hexanoic acid. This compound has the formula:

EXAMPLE IV 4-hydroxydecanoic acid, 'y-lactone A mixture of 56.1 grams (0.5 mole) of n-octene-l and 167 grams (1.0 mole) of ethyl bromoacetate was heated to A solution of 12.1 grams (0.05 mole) of benzoyl peroxide in 167 grams (1.0 mole) of ethyl bromoacetate was added d-ropwise, with stirring, during 5.5 hours, holding the temperature of the reaction mixture at 90. The mixture was stirred at 90 for an additional 2 hours and allowed to stand overnight. The dark mixture was then distilled at 20 millimeters, giving about 300 milliliters of ethyl bromoacet'ate, boiling point 5961. When all of the ethyl bromoacetate was off and the vapor temperature began to drop, the pressure was changed to 55 millimiters and the mixture was refluxed for 3 hours (vapor temperature was Then the liquid was distilled, using a six inch electrically heated, helix-packed column. After a 10 gram forerun, boiling point 127-133", a 65.7 gram fraction of crude lactone, boiling point 140- /15 millimeters of mercury, was obtained. The crude material was refluxed with 30 grams of sodium hydroxide in 300 milliliters of water for 1 hour, giving a clear, yellow solution. The solution was cooled and washed with three 200 milliliter portions of ethyl ether for removal of non-acidic substances. Acidification of the basic layer with dilute sulfuric acid gave a yellow, organic upper layer. The organic layer was separated and refluxed with 5 milliliters of concentrated hydrochloric acid for 5 hours for lactonization of the hydroxy acid. Benzene was added and water and hydrochloric acid were removed by azeotropic distillation. After removal of remaining benzene the liquid was fractionally distilled, giving 34.1 grams (40 percent theory based on starting octene) of 4-hydroxydecanoic acid, 'y-lactone, boiling point l05106/ 3 millimeters of mercury, n 1.4528. The infrared spectrum agreed with the structure:

EXAMPLE V 4-hydr0 xyddccan0ic acid, 'y-lactone A solution of 20 grams of 4-ketolauric acid in 100 milliliters of dry, thiophene-free benzene was treated with 0.2 gram of Adams catalyst and reduced at 190 for 12 hours under 1100 psi. of hydrogen in a rocking pressure vessel. The mixture was filtered free of catalyst, and the filtrate was freed of benzene at the water pump. The residual material was partitioned with ethyl ether versus pH 9 butter, the lactone going to the ether layer. In this way a total of 10.2 grams (55 percent of theory) of essentially pure lactone was obtained. Distillation of this material, using a 6 inch, electrically heated, helix-packed column, gave 5.1 grams of 4-hydroxydodecanoic acid, -lactone, boiling point 128-130/23 millimeters of mercury, n 1.4498.

EXAMPLE VI 4-hydr0wtetradecan0ic acid, 'y-lactone A 14.5 gram sample of 4ketomyristic acid in 100 milliliters of dry, thiophene-free benzene with 0.2 gram of Adams catalyst was reduced catalytically at 220 under 1200-1350 p.s.i. hydrogen in a rocking pressure vessel for 14 hours. The resulting solution was filtered free of catalyst, and the filtrate was pulled down at the water pump until free of benzene. The residual oil was partitioned, using ethyl ether versus aqueous sodium carbonate (200 milliliter layers of each) in a normal 3 (funnel series. The upper layers were combined, dried over anhydrous sodium carbonate, filtered, and freed of ether at the water pump to leave 8.7 grams of mixed oil and solid. Recrystallization of this material from Skellysolve A gave 4.9 grams (36 percent of theory) of 4-hydroxytetradecanoic acid, 'y-lactone, a white, crystalline solid, melting point 2829.

It has been found that the tobacco additives of the invention when incorporated into tobacco products impart a flavor and aroma both before and during smoking which many smokers consider to be desirable in smoking products. However, it is pointed out that the methods for defining or characterizing the quality of a flavor or aroma in the tobacco art are almost purely subjective and different smokers may define the same flavor quite differently. Also, the compounds included within the broad scope of this invention may impart different flavors or aromas depending upon the alkyl substituents therein. Thus, the compounds comprehended by this invention, by subjective tests, impart characteristic flavors which are desirable in tobacco products and the smoke therefrom even though the exact character thereof cannot be described on the basis of known standards. The tobacco additive of Example I imparts an aroma or flavor which is reminiscent of burley tobacco which many smokers consider to be desirable in a tobacco product. The aroma or flavor of the other additives may vary with variation in the length of the straight-chain alkyl substituents. Thus, for example, the additive 4-hydroxytetradecanoic acid, 'y-lactone, imparts an aroma reminiscent of peaches.

In accordance with this invention, a compound embraced by generic Formula I or mixtures thereof is added to tobacco or applied to a smoking article or its component parts in amounts of about 0.0001 to 2.0 percent by weight of the product. Preferably the amount of additive is between about 0.01 and 0.5 percent by weight in order to provide a tobacco product having a desired flavor and aroma. However, the amount used will depend upon the amount of flavor and aroma desired and the particular compound or mixture thereof that is used. The additive may be incorporated at any step in the treatment of the tobacco but is preferably added after aging, curing and shredding and before the tobacco is formed into cigarettes. Likewise, it will be apparent that only a portion of the tobacco need be treated and the thus treated tobacco may be blended with other tobaccos before the cigarettes or other smoking articles are formed. In such case the tobacco treated may have the additive in excess of the amounts above indicated so that when blended with other tobaccos the final product will have the percentage within the indicated range.

In accordance with one specific embodiment of this invention, an aged, flue-cured and shredded tobacco is sprayed with a 1% ethyl alcohol solution of 4-hydroxyoctanoic acid, -lactone in an amount to provide a tobacco containing 0.025 percent by weight of the additive on a dry basis. Thereafter the alcohol is removed by evaporation and the tobacco is manufactured into cigarettes by the usual techniques. It has been found that the cigarette when prepared as indicated has a desired and pleasing flavor, an aroma which to some people is reminiscent of coconut and is detectable and pleasing in the main and side smoke streams when the cigarette is smoked.

The additives falling within the scope of this invention may be applied to the tobacco by spraying, dipping or otherwise, utilizing suitable suspensions or solutions of the additive. Thus water or volatile organic solvents, such as alcohol, ether, acetone, volatile hydrocarbons and the like, may be used as the carrying medium for the additive while it is being applied to the tobacco. Also, other flavorand aroma-producing additives, such as those disclosed in United States Patents Nos. 2,766,145, 2,905,575, 2,905,576, 2,978,365 and 3,041,211 may be incorporated into the tobacco with the additive of this invention.

While this invention is principally useful in the manufacture of cigarette tobacco, it is also suitable for use in connection with the manufacture of pipe tobacco, cigars or other tobacco products. Furthermore, the compounds may be added to certain tobacco substitutes of natural or synthetic origin and by the term tobacco as used throughout this specification is meant any composition intended for human consumption by smoking or otherwise, whether composed of tobacco plant parts or substitute materials or both.

Also, the invention has been particularly described with reference to the addition of the compounds directly to tobacco. However, it will be apparent that the compound may be applied to the paper of the cigarette or to the wrapper of a cigar. Also it may be incorporated into the filter tip, the packaging material or the seam paste employed for gluing the cigarette paper. Thus a tobacco product is provided which includes the specified additives and tobacco although in every instance the compound need not be admixed with the tobacco as above specifically described.

While several particular embodiments of this invention are shown above, it will be understood, of course, that the invention is not to be limited thereto, since many modifications may be made, and it is contemplated, therefore, by the appended claims, to cover any such modifications as fall within the true spirit and scope of this invention.

We claim: 1. A tobacco product having added thereto an amount suflicient to alter the flavor or aroma of a tobacco product of a compound selected from the group of compounds having the formula:

where -R is a straight-chain alkyl group of from 1 to carbon atoms.

2. The product recited in claim 1 wherein the amount of said compound is between about 0.0001 and 2.0 percent by weight of the product.

3. The product recited in claim .1 wherein the amount of said compound is between about 0.01 and 0.5 percent by weight of said product.

4. A tobacco product having added thereto and dis persed therein a small amount suflicient to improve the flavor thereof of 4hydroxypentanoic acid, 'y-lactone.

5. The product of claim 4 wherein the amount of the said flavorant is between about 0.0001 and 2.0 percent by weight of said product.

6. A tobacco product having added thereto and dispersed therein a small amount sufiicient to improve the flavor thereof of 4-hydroxyhexanoic acid, 'y-lactone.

7. The product of claim 6 wherein the amount of the said flavorant is between about 0.0001 and 2.0 percent by weight of said product.

.8. A tobacco product having added thereto and dispersed therein a small amount sufiicient to improve the flavor thereof of 4-hydroxyheptanoic acid, 'y-lactone.

9. The product of claim 8 wherein the amount of the said flavorant is between about 0.0001 and 2.0 percent by weight of said product.

v10. A tobacco product having added thereto and dispersed therein a small amount sufiicient to improve the flavor thereof of 4-hydroxyoctan oic acid, 'ylactone.

11. The product of claim 10 wherein the amount of the said flavorant is between about 0.0001 and 2.0 percent by weight of said product.

12. A tobacco product having added thereto and dispersed therein a small amount suflicient to improve the flavor thereof of 4-hydroxynonanoic acid, -lactone.

13. The product of claim 12 wherein the amount of the said .tlavorant is between about 0.0001 and 2.0 percent by weight of said product.

14. A tobacco product having added thereto and dispersed therein a small amount suifi-cient to improve the flavor thereof of 4-hydroxyunde canoic acid, v-lactone.

15. The product of claim 14 wherein the amount of the said flavo-rant is between about 0.0001 and 2.0 percent by weight of said product.

1 6. A tobacco product having added thereto and dispersed therein a small amount sufiicient to improve the flavor thereof of 4-hydroxydodecanoic acid, lactone.

17. The product of claim 16 wherein the amount of the said flavorant is between about 0.0001 and 2.0 percent by weight of said product. p

18. A tobacco product having added thereto and dis persed therein a small amount sufiicient to improve the flavor thereof of 4-hydroxytetradecanoic acid, 'y-lactone.

19. The product of claim '18 wherein the amount of the said flavorant is between about 0.0001 and 2.0 percent by weight of said product.

2 0. A process for improving the flavor of a tobacco product which comprises adding thereto a small amount of a compound selected from the group of compounds having the formula:

References Cited UNITED STATES PATENTS 2,706,147 10/1956 Rowland 2,872,360

131 17 3/1959 Teague 131264 X SAMUEL KOREN, Primary Examiner. MELVIN D. REIN, Examiner. 

1. A TOBACCO LPRODUCT HAVING ADDED THERETO AN AMOUNT SUFFICIENT TO ALTER THE FALVOR OR AROMA OF A TOBACCO PRODUCT OF A COMPOUND SELECTED FROM THE GROUP OF COMPOUNDS HAVING THE FORMULA: 5-R-TETRAHYDROFURAN-2-ONE WHERE R IS A STRAIGHT-CHAIN ALKYL GROUP OF FROM 1 TO 10 CARBON ATOMS. 